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Electrophoretic Crystallization of Ultrathin High-performance Metal-organic Framework Membranes
Published on: August 16, 2018
La captura selectiva de cationes metálicos por marcos metálicos-orgánicos aniónicos blandos a través de drásticas
Jian Tian1, Laxmikant V Saraf, Birgit Schwenzer
1Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
Journal of the American Chemical Society
|May 29, 2012
Resumen
Los marcos metálicos orgánicos aniónicos flexibles (MOF) se transforman en sistemas neutros a través de la inserción de cationes. Este proceso altera el tamaño del marco y permite la absorción selectiva de metales de transición sobre metales alcalinos.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Química es la química.
Sus antecedentes:
- Las estructuras metálico-orgánicas aniónicas (MOF) son materiales versátiles con propiedades sintonizables.
- Las transformaciones monocristalinas a monocristalinas ofrecen una modificación controlada del material.
Objetivo del estudio:
- Para investigar la transformación de MOFs aniónicos flexibles en sistemas heterobimetálicos neutros.
- Explorar los cambios estructurales y la selectividad catiónica durante estas transformaciones.
Principales métodos:
- Transformación de un solo cristal a un solo cristal (SC-SC) a través de la inserción de cationes.
- Caracterización de la estructura del MOF y la dinámica del marco.
- Investigación de la selectividad de la captación de cationes utilizando varios iones metálicos.
Principales resultados:
- Los MOF aniónicos se convirtieron con éxito en sistemas heterobimetálicos neutros.
- Los marcos exhibieron cambios significativos en el volumen (hasta un 33%) debido a la dinámica de los bonos cooperativos.
- Los MOF demostraron una alta selectividad para los cationes de metales de transición divalentes (Co2 +, Ni2 +) sobre los cationes de metales alcalinos (Li +, Na +).
Conclusiones:
- La inserción catiónica proporciona una vía para la transformación controlada de MOF.
- Los MOF flexibles pueden sufrir cambios estructurales sustanciales mientras mantienen la cristalinidad.
- Estos MOF transformados son prometedores para la separación y captura selectiva de iones metálicos.
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